Test round-trip JSON procedure parameter.

Author: bgrainger

docs/content/tutorials/migrating-from-connector-net.md

@@ -262,4 +262,5 @@ The following bugs in Connector/NET are fixed by switching to MySqlConnector. (~
 * [#101252](https://bugs.mysql.com/bug.php?id=101252): Can't query `CHAR(36)` column containing `NULL`
 * [#101253](https://bugs.mysql.com/bug.php?id=101253): Default value for `MySqlParameter.Value` changed from null to `0`
 * [#101302](https://bugs.mysql.com/bug.php?id=101302): Stored Procedure `BOOL` parameter can only be mapped to `MySqlDbType.Byte`
+* [#101485](https://bugs.mysql.com/bug.php?id=101485): Stored Procedure `JSON` parameter throws “Unhandled type encountered” `MySqlException`
 * [#101507](https://bugs.mysql.com/bug.php?id=101507): `MySqlCommand.Cancel` throws `NullReferenceException` for a closed connection

tests/SideBySide/StoredProcedureTests.cs

@@ -671,6 +671,19 @@ public void DeriveParametersSetJson()
 				AssertParameter("@vJson", ParameterDirection.Input, MySqlDbType.JSON));
 		}
 
+		[SkippableFact(ServerFeatures.Json, Baseline = "https://bugs.mysql.com/bug.php?id=101485")]
+		public void PassJsonParameter()
+		{
+			using var cmd = new MySqlCommand("SetJson", m_database.Connection);
+			cmd.CommandType = CommandType.StoredProcedure;
+			var json = "{\"prop\":[null]}";
+			cmd.Parameters.AddWithValue("@vJson", json).MySqlDbType = MySqlDbType.JSON;
+			using var reader = cmd.ExecuteReader();
+			Assert.True(reader.Read());
+			Assert.Equal(json, reader.GetString(0).Replace(" ", ""));
+			Assert.False(reader.Read());
+		}
+
 		private static Action<MySqlParameter> AssertParameter(string name, ParameterDirection direction, MySqlDbType mySqlDbType)
 		{
 			return x =>